A policy may contain additional provisions not inconsistent with this chapter and which are:
(a) Required to be inserted by the laws of the insurer's domicile;
(b) Necessary, because of the manner in which the insurer is constituted or operated, in order to state the rights and obligations of the parties; or
(c) Desired by the insurer and not prohibited by law nor in conflict with any provisions required to be included therein and which are considered reasonable and just.